<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>UserInfo</title>
    <script>
        function a() {
            alert("hello")
        }
    </script>
</head>
<body>
    <a href="https://www.baidu.com">aaaaa</a>
    <button id="btn1" onclick="a()">点我</button>
</body>
</html>